<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script>
			var time = prompt('请输入0-60之间的一个数字');
			
			// time < 10 ? time = '0' + time : time=time;
			// alert(time);
			
			var resut = time < 10 ? '0'+time : time;
			alert(resut);
		</script>
	</head>
	<body>
	</body>
</html>
